One person has died and seven people are unaccounted for after a 3.6-magnitude earthquake struck the Italian resort island of Ischia, police say.

Giovanni Vittozzi of the civil protection department told Sky TG24 that several buildings in Casamicciola town had collapsed.

He said one woman was killed and seven people are unaccounted for, and the Rizzoli Hospital has been evacuated, except for patients on respirators.

The quake rattled the island at the peak of tourist season, cutting electricity and sending panicked residents and tourists into the streets.

The earthquake hit the popular Italian tourist island of Ischia, off the coast of Naples (Image: AFP/Getty Images)

Earthquake victims are rescued from the rubble (Image: AFP/Getty Images)

Italy's national volcanology institute said it struck just before 9pm local time, just as many people were having their evening meals. News reports suggested the hardest-hit area was Casamicciola, on the northern part of the island.

A doctor at the Rizzoli Hospital, Roberto Calloca, told Sky TG24 that 20 people were being treated for minor injuries at a makeshift emergency room set up in the hospital grounds.